There are many applications in which it is desirable to analyze a digital video data stream in order to identify scene changes (as used herein, the phrase "video data stream" is intended to encompass any series of digital image frames, whether they comprise a full motion video or simply a sequence of discrete "still" images). For example, it is common for video footage for a larger work to be shot in the most convenient order, rather than in the order of the final larger work. An editor then assembles various portions of the video footage into the desired sequence of the final work. Similarly, a news reporting video may be pieced together from many video segments recorded at different times and places. In such situations, it is convenient to identify what scenes are contained in each piece of video footage (which may be sorted on separate video cassettes, for example) so that the appropriate scene may be readily located by the editor when it is needed in the editing process.
Because such video information may be easily digitized into a digital video data stream, it is known in the prior art to analyze the video data stream frame by frame (usually using computer software) in order to determine the boundaries of individual scenes. The software program performing this analysis must therefore be configured to interface with the video digitizing hardware in order to request input of each frame in the video data stream. Because of this direct connection to the digitizing hardware, such software can realistically work with only a limited number of hardware configurations (usually one or two). If the user desires to use a new hardware configuration, new scene detection software must be purchased or written.
Such intimate association between the scene detection software and the video input hardware severely limits the usefulness of the software and greatly increases its price. There is therefore a need for a method and apparatus for detecting scene changes in a digital video stream which overcomes this problem. The present invention is directed toward meeting this need.